Automatic control for carburetor choke valves



June 13, 1933.

D. w. GRIFFITH ET AL ,913,541

"AUTOMATIC CONTROL FOR CARBURETOR CHOKE VALVES 2 Sheets-Sheet 1 Filed June 10, 1931 1 2 6 6a 2 Z w 2 E622 Era. J

pfw/ 'y w /Fflffi OEV/LLE 51 5547775 ATTORNEY June 1933- D. w. GRIFFITH ET AL 1,913,541

AUTOMATIC CONTROL FOR CARBURETOR CHOKE VALVES Filed June 10, 1931 2 Sheets-Sheet 2 MIIIIII ATTORNEY whereby the choke valve may 0 Patented June 13, 1933 UNITED STATES PATENT OFFICE DEWITT W. GB VIFFITH AND ORVILLE S.

BEATTIE, OF SAN DIEGO, CALIFORNIA,

ASSIGNOBS OI ONE-TENTH TO LEO J. DEHZEBS, OF SAN DIEGO, CALIFORNIA AUTOIATIC CONTROL FOB CABBURETOR CHOKE VALVES Application filed June 10,

Our invention relates to automatic control for carburetor choke valves and the objects of our invention are:

First, to provide a control of this class which prevents over-choking of the carburetor particularly when the motor is cold, thereby eliminating the danger of oil dilution and excessive formation of carbon in the cylinders due to this cause;

Second, to provide a control of this class which eliminates any need of a hand control for the choke valve of'a carburetor;

Third, to provide a thermostat actuated control of this class-wherein the thermostat is subjected to the'direct heating action of the exhaust gases of an engine with which .it is associated, only during the warming up interval of the engine, thereby preventing overheating of the thermostat;

Fourth, to provide a novel control of this class which has incorporated therein a novelly constructed valve for regulating the flow of heated gases from the exhaust pipe to the thermostat element of the contro Fifth, to provide a control of this class which is particularly compact, and easily installed on practically any make of vehicle;

Sixth, to provide acontrol of this class 11. against the action of the control shoul the motor be faced unduly when cold thus preventing flooding of the carburetor and the evils occasioned thereby;

Seventh, to provide a control which though permitting the choke valve to open against the action of the control, positively holds the choke valve in its open position once the motor has been warmed up, thus preventing the choke valve from closing accidentally; and

Eighth, to provide on the whole a novelly constructed automatic control for carburetor choke valves which is particularly simple of construction, and of o ration, durable, efiicient in its action and which will not readily deteriorate or get out of order.

With these and other objects in view as will appear hereinafter, our invention consists of certain novel features of construction, combination and arrangement of parts 1931. Serial N0. 543,356.

and portions as will be hereinafter described in detail and particularly set forth in the appended claims, reference being had to the accompanying drawings and to the characters of reference thereon which form a part of this. application, in which:

Figure 1 is an elevational view of our automatic control for carburetor choke valves as it appears when the engine is heated showing a carburetor in outline and adjacent portions of the exhaust manifold in section; Fig. 2 is an enlarged sectional view through 2-2 of Fig. 1 with parts and ortions shown in elevation; Fig. 3 is an en arged sectional View through 3-3 of Fig. 2 with parts and portions shown in elevation and with the cap member removed; Fig. 4 is an enlarged sectional view taken through 4-4 of Fig. 1 with parts and portions shown in elevation; Fig. 5 is a longitudinal sectional View of the connecting mechanism between the control and choke valve lever with parts and portions as shown in elevation; and Fig. 6 is a transverse sectional view through 6-6 of Fig. 2.

Similar characters of reference refer to similar parts and portions several views of the drawings.

Nipple 1, valve housing 2, ball valve 3, cam member 4, frame 5, journal shaft 6, cage 7, thermostat element 8, shaft 9, pinion gear 10, lever arms 11 and 12, connecting rod 13, cover 14, lever arm 15, end member 16, connecting rod 17, end member 18, lever arm 19, choke valve shaft 20, choke valve 21, sleeve 22, and spring 23 constitute the principal parts and portions of our novel automatic control for choke valves.

Our automatic control for carburetor choke valves is adapted to be operated by the heated gases passing through the exhaust manifold. To this end a stem or nipple 1 is secured in the wall of the exhaust manifold A. Secured to the upper end of the nipple '1 is a valve housing 2 which is provided with a vertical passage 2a therethrough intersected intermediate its ends by a cross opening 2?). Below the cross opening, the passage 21; is constricted so as to. form a throughout the valve seat 20 which is adapted to coact in a ball valve 3. I

The transverse opening 21) is" adapted to receive a valve closin cam 4. The cam 4 includes a pair of cy indrical journal portions 4w adapted to Journal in the portions of the cross opening 2b on either side of the passage 2a,. The ]0l1IIl3.l portions 4a are connected across the passage 20 by a cam portion 46. The cam ortion 4b is so arranged-that in one position it engages the ball valve 3 and holds it firmly against the valve seat 20 as shown best inFig. 3.

The cam portion 4?) is adapted to be shifted from the dotted position shown in Fig. 3 to the solid line position shown therein durin the warming up period of the en- 'ne. T us when the engine is cold and uring the warming up period, the ball .valve 3 is free to act as a check valve and allow an upward flow of hot exhaust gases from the exhaust manifold through the passage Qw of the valve casing 2. During the passage of gases through the valve, the ball isconstantly agitated so that soot or other particles of solid matter in the exhaust gases cannot collect or form on the ball or adjacent portions of the valve structure so as to prevent proper operation thereof The upper end of the valve casing 2 1s secured to a frame member 5. The frame member 5 is provided with a disc shaped base portion 5a to which is attached the valve casing 2. The base portion 5a is provided with a diametrically extending ridge at the ends of which a pair of upwardly directed parallel disposed arms 5?) are arranged inwardly from the periphery of the base 5b. The valve casin 2 is located directly underneath the ri ge 5c. Passages 50? extend from the passage 2a upw ardly through the ridge 50 as shown in Figs. 2 and 3. I

A short distance above the ridge 50 the arms 50 are connected by a journal rod 6 upon which is mounted a journal portion 7a of a cage member 7 in the form of a rectangular loop. The extremities of the journal portion 7w are provided with upwardly directed arm portions 712 which are in turn connected at their extremities by a cross portion arran ed in parallel disposed relation with the 3ournal portion 7a. Thecross portion 7 c is provided with an arcuate gear segment 7d arranged with its center of curvature coinciding with the axis of the journal rod 6.

A thermostat element 8 is provided which is wound in the form of a spiral, the one end of which is secured to the journal portion 7 a of the cage 7 while the other end thereof is secured to one side of the ridge portion 5a of the frame 5 as shown best in Fig. 3. The arms 5? support a shaft 9 at their extremitles WhlCh extends over the gear segment 7d and is provided with a pinion gear 10 which meshes with the gear segment.

The shaft 9 protrudes from one of the I arms 5b. The cam member 4 is provided with a stem 40 which extends in parallel disposed relation with the shaft 9.. The stem 4c and the shaft 9 are connected by a pair of lever arms 11 and 12 and a connecting link 13. The shaft 9 and stem 40 are so connected that when the thermostat is in its cold position wherein the various. parts are in the position shown by dotted lines in Fig. 3, the ball valve 3 isfree to allow a flow of exhaust gases through the valve passage 2a, passages 5d and against the thermostat element. As the thermostat element warms, the various moving parts shift to the position shown by solid lines in the several views closing the valve 3 whereby a direct flow of the exhaust gases against the thermostat element is prevented. The nipple 1 and valve casing 2 as well as the frame 5 are made of sufiiciently thick heat conducting material whereby once the thermostat element has been heated and the valve closed, the heat conducted by the metal constituting the above parts is suflicient to maintain the thermostat element in a heated condition so that the choke valve is maintained in its open position. This is facilitated by a cover member 14 which fits over the legs 5?; of the frame and is secured to the base portion 5a thereof. The cover portion is provided with a slit 14a: in one of the side walls through which extends the shaft 9. The slit 14a is lon enough to permit insertion of the frame an shaft as a unit into the cover. Small openings 14?) are provided in the top of the cover in order to facilitate the flow of gases therethrough.

Also mounted on the shaft 9 is a lever arm 15. The extended end of the lever arm 15 journals the bifurcated end 161 of an end member 16 which forms a part of a connecting means joining the shaft 9 with the shaft which supports the choke valve. The end member 16 is provided with an internall threaded hollow shank portion 16b whic extends from the bifurcated end 1612. The shank portion 16b receives'a screw threaded end 170: of a connecting rod 17.

The other end of the connecting rod 17 is slidably mounted in a tubular shank portion 180: of a second end member 18. Said second end member is also provided with a bifurcated end 186 which isadapted to be joined to a lever arm 19. The lever arm 19 is in turn secured to the shaft 20 of a conventional choke valve 21 mounted in the air intake of the carburetor B.

The bifurcated portion 812 of the end member 18 forms a pair of diametrically disposed longitudinally extending slots 18c arranged inwardly from the extremity of said end member. A cross pin 17b is secured in the corresponding end of the connecting rod 17 to slide in the slots 180 in such a manner as whereby the connecting rod 17 is prevented from rotation with respect to the end'member 18.

' A short sleeve member 22 is mounted upon the connecting rod 17 adjacent the end member 16so as to cover up the otherwise exposed portions of the screw threads 170. A spring 23 is coiled about the connecting rod 1.7 and yieldably engages the adjacent ends of the end member 18 and the sleeve 22, whereby the end members 16 and 18 are normally held in their extended relation as shown by solid lines in the several views.

Operation of our automatic control for carburetor choke valve is as follows: When the engine is cold, the several parts are m the dotted line position shown in Figs. 1 and 3. Should the driver attempt to race the engine when the control and choke valve are in their closed positions, the flow of air through the carburetor causes the choke valve 21 to shift against the action of the spring 23 so that the choke valve opens sufficiently to prevent flooding of the carburetor. It should be here noted that the choke valve in many makes of carburetors 1s unbalanced; that is, the area is larger on one side of its axis than on the other. Hence the flow of air into the carburetor tends to turn the choke valve to its open position. When the engine is idling, but is still cold, the choke valve is almost closed. The end member 16 .is so adjusted that the tension of the spring is just sufiicient to permit movement of the choke valve before the suction through the carburetor has reached the point necessary to draw in excess fuel. During the warming up period of the engine, a portion of the exhaust gases passes through the valve casing 2 and strikes the thermostat element so as to heat thesame. and at the same time heats the stem 1, valve' housing 2, frame 5 and the cover 14. As soon as the thermostat elem ent has warmed sufliciently. the cam member 4 closes the valve formed by the ball member 3 and valve seat 20, therebv stopping the flow of exhaust gases through the control. The thermostat is now maintained in its heated condition by conduction. This arrangement prevents the'control valve from becoming over-heated, therebv greatly prolonging its effective life. As the choke valve opens by action of the control. less and less suction is possible through the intake passage of the carburetor, whereupon the spring 23 becomes inoperative. I

Though we have shown and described a particular construction. combination and arrangement of parts and portions, we do not wish to be limited to this particular construction, combination and arrangement, but desire to include in the scope of our invention the'construction, combination and ararranged tov direct rangement substantially as set forth in the ap ended claims.

aving thus described our invention, what we claim as new and desire to secure by Letters Patent is:

1. In an automatic control for carburetor choke valves, a casing formed of heat conducting material and connected with an engine so as to be readily responsive to the heating action of said engine, a thermostat element mounted in said casing, lever and link means connecting said thermostat element with an unbalanced carburetor choke valve, said link means being yieldable to movement of said choke valve in opposition to the tendency of said thermostatelement.

'2. In an automatic control for carburetor choke valves, a casing formed of heat con;- ducting material and connected with the exhaust manifold of an engine, a thermostat element mounted in said casing, said casing provided with a assage communicating with the interior 0 said exhaust manifold exhaust gases through said thermostat element, and link and lever means connecting said thermostat element with an unbalanced carburetor choke valve.

3. In an automatic control for carburetor choke valves, a casingformed of heat conducting'material and connected with the exhaust manifold of an engine, a thermostat element mounted in said casing, said casing provided with a passage communicating with said exhaust manifold arranged to direct exhaust gases against said thermostat element, and link and lever means connecting said thermostat element with an unbalanced carburetor choke valve, said link means being said passage against said thermostat element.

A. In an automatic control for carburetor choke valves, a casing formed of heat conducting material and connected with the exhaust manifold of an engine, a thermostat element mounted in said casing, said casing provided with a passage communicating with said exhaust manifold arranged to direct exhaust gases against said thermostat element, link and lever means connecting said thermostat element with a carburetor choke valve, a valve disposed in said. passage, and connecting means joining the movement of said valve with said link and lever means, whereby said valve is caused to close said passage upon heating of said thermostat a predetermined amount.

5. In an automatic control for carburetor choke valves, a casing formed of heat conducting material and connected with the exhaust manifold of an engine, a thermostat element mounted in said casing, said casing provided with a passage communicating with said exhaust manifold arranged to diyieldable to movement of said' choke valve in opposition to the tendency of rect exhaust gases against said thermostat element, link and lever means connecting said thermostat element with an unbalanced carburetor choke valve, said link means being yieldable to movement of said choke valve in opposition to the tendency of said thermostat element, a valve disposed in said passage, and connecting means joining the movement of said valve with said link and lever means, whereby said valve is caused to close said passage upon heating of said thermostat a predetermined amount.

6. In an automatic control for carburetor choke valves, a casing formed of heat conducting material and connected with the exhaust manifold of an engine, a thermostat element mounted in said casing, said casing provided with a passage communicating with said exhaust manifold arranged to direct exhaust gases against said thermostat element, link and lever means connecting said thermostat element with an unbalanced carburetor choke valve, a check valve disposed in said passage, cam means for locking said check valve in a closed position, and means connecting said cam means with said thermostat whereby said cam means is caused to lock said check valve in its closed position upon heating of said thermostat 'a predetermined amount.

7. In an automatic control for carburetor choke valves, a casing formed of heat conducting material and connected with the exhaust manifold of an engine, a thermostat element mounted in said casing, said casing provided with a passage communicating with said exhaust manifold arranged tn direct exhaust gases against said thermostat element, link and lever means connecting Isaid thermostat element with an unbalanced carburetor choke valve, said link means hemg yieldable to movement of said choke va ve in opposition to the tendency of said thermostat element, a check valve disposed in said passage, cam means for locking said check valve in a closed position, and means connecting said cam means with said thermostat whereby said cam means is caused to lock said check valve in its closed position' upon heating of said thermostat a predetermined amount.

8. The combination with an unbalanced carburetor choke valve, a shaft rotatably supportingsaid choke valve, and a readily heated portion of an engine, of a casing formed of heat conducting material and connected with said readily heated portion of an engine, a thermostat element mounted in said casing, a rod rotatable by said thermostat element, levers of said choke valve shaft and said rod, means connecting said levers including apair of telescopable members,-

and yieldable means tending to retain said telescopable members in their one extreme relation, said connecting means disposed so that said yieldable means is responsive to movement of said choke valve in opposition to said thermostat element.

9. The combination with an unbalanced carburetor choke valve, a shaft rotatably supporting said choke valve, and the exhaust manifold of an engine, of a casing formed of heat conducting material and connected with said exhaust manifold, a thermostat element mounted in said casing, said casing provided with a passage communicating'with said exhaust manifold arranged to direct exhaust gases against said thermostat element, a rod rotatable by said thermostat element, levers of said choke valve shaft and said rod, means connecting said levers including a pair of telescopable members, and yieldable means tending to retain said telescopable members in their one extreme relation, said connecting means disposed so that said yieldable means is responsive to movement of said choke valve in opposition to said thermostat element.

10. The combination with an unbalanced carburetor choke valve, a shaft rotatably supporting said choke valve, and the exhaust manifold of an engine, of a casing formed of heat conducting material and connected with said exhaust manifold, a thermostat element mounted in said casing, said casing provided with a passage communicating with said exhaust manifold arranged to direct exhaust gases against said thermostat element, a rod rotatable by said thermostat element, levers of' said choke valve shaft and said rod, means connecting said levers including a pair of telescopable members, yieldable means tending to retain said telescopable members in their one extreme relation, said connecting means disposed so that said yieldable means is responsive to movement of said choke valve in opposition to said thermostat element, a check valve disposed in said passage, cam means for locking said check valve in a closed position, and means connecting said cam means with said thermostat whereb said cam means is caused to lock said checii valve in its closed position upon heating of said thermostat a predetermined amount.

11. The combination with an unbalanced carburetor choke valve, a shaft rotatably supporting said choke valve, and the exhaust manifold of an engine, of a casing formed of heat conducting material and connected with said exhaust manifold, a thermostat element mounted in said casing, said casing provided with a passage communicating with said exhaust manifold arranged to-direct exhaust gases against said thermostat element, a rod rotatable by said thermostat element, levers of said choke valve shaft and said rod, means connecting said levers including a pair of telescopable members, yieldable means tending to retain said telescopable members in their one extreme relation, said connecting means disposed so that'said yieldable means is responsive to movement of said choke valve in opposition to said thermostat element, a 'valve disposed in said passage, and connecting means joining the movement of said valve with said thermostat rod, whereby said valve is caused to close said passage upon heating of said thermostat a predeterm1ned I amount.

12. The combination with an automatic thermostat control for carburetor valves adapted to be operated by heat from an engine exhaust manifold, of a valve disposed so as to control the flow of gases from said exhaust manifold to the thermostat element of said control, said valve includingya casing, a normally loose ball valve and seat so therefor arranged in said casing, and a cam means arranged to engage said ball valve and to hold said ball valve in sealed relation with said seat. V

13. In a device of the class described, a

thermostat element, a casing therefor provided with a passage in communication with an exhaust manifold of an engine, a ball valve and seat therefor arranged in said Passage, and a cam means arranged to engage said ball valve and to hold said ball valve upon said seat.

14. The combination with an automatic thermostat control ,for carburetor valves adapted to be operated by heat from an engine exhaust manifold, of a valve disposed so as to control the flow of gases from said exhaust manifold to the thermostat element of said control, said valve including, a casing, a normally loose ball valve and seat.

40 therefor arranged in said casing, a cam means arranged to engage said ball valve and to hold said ball valve in sealed relation with said seat, and means actuated by said I thermostat element for operating said cam means so as to close said valve when said thermostat element attains a predetermined temperature.

15. In a device of the class .described, a thermostat element, a casing therefor provided with a passage, in communication with an exhaust manifold .of an engine, a ball valve and seat therefor arranged in said passage, a cam -means arranged to engage said ball valve and to hold said ball valve upon said seat, and means actuated by said thermostat element for operating said cam means so as to close said valve when said thermostat element attains a predetermined temperature.

a In testimony whereof, we have hereunto set our hands at San Diego, California, this 4th day of June, 1931.

DEWITT w. GRIFFITH. ORVILLE s. BEATTIE. 

